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            <h2 class="title" style="clear: both"><a id="dbstream"></a>Dbc::db_stream()</h2>
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      <pre class="programlisting">#include &lt;db_cxx.h&gt;
 
int
Dbc::db_stream(DbStream **dbs, u_int32_t flags);  </pre>
      <p>
         The <code class="methodname">Dbc::db_stream()</code> method points to a
         key/value pair where the data item is an external file. 
	 Use the <span class="bold"><strong>flags</strong></span> parameter
         to indicate whether the stream is to be opened for reading, or for
         reading and writing.
     </p>
      <p>
         Once the stream is opened, you read it using <a class="xref" href="dbstream_read.html" title="DbStream::read()">DbStream::read()</a>, and
         you write to it using <a class="xref" href="dbstream_write.html" title="DbStream::write()">DbStream::write()</a>. 
     </p>
      <p>
         Close this stream using <a class="xref" href="dbstream_close.html" title="DbStream::close()">DbStream::close()</a>.
     </p>
      <p>
         If the data item is not an external file, this method returns an
         error.
     </p>
      <p>
         Unless otherwise specified, the
         <code class="methodname">Dbc::db_stream()</code> <span>
            
            <span>
                method either returns a non-zero error value or throws an
                exception that encapsulates a non-zero error value on
                failure, and returns 0 on success.
            </span>
        </span>
    </p>
      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
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            <div>
              <h3 class="title"><a id="idm139670054474864"></a>Parameters</h3>
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        <div class="sect3" lang="en" xml:lang="en">
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              <div>
                <h4 class="title"><a id="idm139670054474128"></a>dbs</h4>
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          <p>
                 The <span class="bold"><strong>dbs</strong></span>
                 parameter references memory into which is copied the newly
                 opened stream.
             </p>
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                <h4 class="title"><a id="idm139670054507088"></a>flags</h4>
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          <p>
                  The <span class="bold"><strong>flags</strong></span> parameter 
                  must be set by bitwise inclusively 
                  <span class="bold"><strong>OR</strong></span>'ing together one or more
                  of the following values:
             </p>
          <div class="itemizedlist">
            <ul type="disc">
              <li>
                <p><a id="blobs_DB_STREAM_READ"></a>
                          <code class="literal">DB_STREAM_READ</code>
                     </p>
                <p>
                         Indicates that the stream is to be opened for
                         read-only access.
                    </p>
              </li>
              <li>
                <p><a id="blobs_DB_STREAM_WRITE"></a>
                          <code class="literal">DB_STREAM_WRITE</code>
                     </p>
                <p>
                         Indicates that the stream is to be opened for
                         read write access. The stream is sync'd to disc when
                         the stream is closed.
                    </p>
              </li>
              <li>
                <p><a id="blobs_DB_STREAM_SYNC_WRITE"></a>
                          <code class="literal">DB_STREAM_SYNC_WRITE</code>
                     </p>
                <p>
                         Indicates that the stream is to be opened for
                         read and write access. The stream is sync'd to disc
                         after each write, instead of when the stream is closed.
                    </p>
              </li>
            </ul>
          </div>
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              <h3 class="title"><a id="idm139670054462304"></a>Errors</h3>
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        <p>
             The <code class="methodname">Dbc::db_stream()</code> <span>
            
            <span>
                method may fail and throw a <a class="link" href="dbexception.html" title="Chapter 6. The DbException Class">DbException</a> 
                exception, encapsulating one of the following non-zero errors, or return one
                of the following non-zero errors:
            </span>
        </span>
        </p>
        <div class="sect3" lang="en" xml:lang="en">
          <div class="titlepage">
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              <div>
                <h4 class="title"><a id="idm139670054441744"></a>EINVAL</h4>
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          <p>
                If the data item is not an external file; or if an invalid flag
                or parameter is specified.
            </p>
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      <div class="sect2" lang="en" xml:lang="en">
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              <h3 class="title"><a id="idm139670054444240"></a>Class</h3>
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        <p>
            <a class="link" href="dbc.html" title="Chapter 3.  The Dbc Handle">Dbc</a>  
        </p>
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      <div class="sect2" lang="en" xml:lang="en">
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              <h3 class="title"><a id="idm139670054469360"></a>See Also</h3>
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        <p>
             <a class="xref" href="blob.html#bloblist" title="External Files and Related Methods">External Files and Related Methods</a> 
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